as you know, in this world of digital media, everyone can live a multi-layered life. And the tsarnaev brothers were no different. Today, abc's alex perez tracked what may have been any hidden part of their lives. Reporter: Friends and classmates describe dzhokhar tsarnaev has an average 19-year-old who didn't talk much when it came to controversial topics. He didn't seem like a bad guy. Reporter: Authoties are zeroing in on every detailf this tsarnaev brothers lives, including social media. Any possible trail of evidence that may lead to answers, like his russian facebook-like page. Abc news brought in a russian translator to pour over the profile. It has several links to islamic websites and pro-chechen websites. And this tweet from last year. A decade in america, already, i want out. Dzhokhar tweeted frequently, including five tweets the day of the bombings. He responded to a friend's tweet, saying, in part, god hates dead people? Or victims of tragedies? Lol. Those people are cooked a year ago, he mentioned the marathon. Boston marathon isn't a good place to smoke. His older brother tamerlan also left behind a social media footprint on youtube, where he created a play list called terrori terrorists. The tsarnaev's aunt who lives in canada. For me to believe that they exited these kinds of atrocities cannot be taken lightly. Convince me. Reporter: She argues their social media lives only show the brothers were curious. Why wouldn't just, you know, just, out of curiosity, tamerlan wouldn't go in there also. Reporter: One of many questions authorities will sift through in the weeks to come. Alex perez, abc news, chicago.

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